Tamping roller foot



Feb. 6, 1951 SMALL 2,541,007

TAMPING ROLLER FOOT Original Filed Aug. 2, 1940 "VI/(g I INVENTOR.fwgefrr i /WELL,

Patented Feb. 6, 1951 UNITED STATES PATENT OFFICE Everett T. Small, Losfi g l t fsf lfazif assignor to J. D. Adams Manufacturing Company,Indian apolis, Ind., a corporation of Indiana 19 .6, Serial .No. 685,311

3 Claims. 1

My invention relates to tamping rollers of the so-called sheeps foottype and has for its object the provision of a foot or tamping elementwhich, in leaving the soil, will not disturb it and thereby interferewith the desired compaction.

In carrying out my invention I employ a circumferential drum, preferablyhollow, to the exterior surface of which there are secured a pluralityof circumferentially extending rows of tamping feet. Each of such feetprojects radially from the drum, is at least as thick, axially of theroller at its outer end as over the remaining portions of its radialextent, and has circumferentially presented side faces which areconcavely curved so that each foot is narrower near the middle of itsradial extent 'than at its ends. As more fully brought out hereinafter,such a foot leaves the soil cleanly without disturbing the soil andthereby lessening the degree of compaction which otherwise would exist.

The accompanying drawing illustrates my invention: Fig. 1 is a sideelevation of a roller with portions thereof broken away to show theconstruction more clearly; Fig. 2 is a plan view of the roller; andFigs. 3, 4, and 5 are related views illustrating the action of eachtamping foot in compacting the soil.

The roller shown in the drawing embodies a generally rectangular framehaving across members l0 and longitudinally extending side members Iinterconnecting the ends of the cross members. Within the rectangularframe thus formed there is rotatably mounted a hollow cylindrical druml2 having in one end wall an opening through which the drum may befilled with varying amounts of water or sand to control the effectiveweight of the roller. Such opening has associated with it a closure 13which prevents loss of the drum-contents. A draw-bar l4 connected to oneof the cross members In and in turn connectible to a tractor or othervehicle enables the roller to be drawn over the surface to be compacted.

Mounted on the cylindrical surface of the drum are an axially extendingseries of pairs of semicircular bands 16. The ends of these bands areturned outwardly to form ears I! (Fig. 3); and clamp bolts l8, extendingbetween the adjacent ears of the two bands of each pair, clamp the bandsfirmly to the drum.

On each of the semi-circular bands l6 there is mounted acircumferentially extending series of tamping feet 20. These feet are ofsubstantially uniform thickness axially of the drum, but theircircumferentially presented faces are con- Divided .and this applicationJuly 22,

2 cavely curved, as ;;will be clear from Fig. 31, .so that each foot, asviewed axially of the drum, will be wider at its ends than at itsmiddle. In the preferred foot-shape, each side face of the footcorresponds substantially to a curve such as would be traced by a pointat ground level on a disk having a radius equal to the distance betweenthe roller-axis and the outer end of the foot and rolling on a planesurface depressed below ground level by a distance equal to the radialextent of the foot. The narrowest portion of a foot so shaped will belocated somewhat nearer to the inner end of the foot than to the outerend, and the radius of curvature of each side face will graduallyincrease from the inner end of the foot to the outer end. Desirably, theinner and outer ends of the foot are of approximately the same width.

Feet of the kind just described have an advantage in operation in thatthey do not tend to pick up the soil being rolled. Since the feet are ofuniform thickness throughout their radial extent andare set in planesperpendicular to the roller axis, there is no tendency to pack the soilbetween the feet of different circumferential series. Owing to the abovedescribed shape of the side faces of the feet, each foot enters andleaves the ground cleanly without picking up any soil. The action ofeach individual foot is illustrated progressively in Figs. 3, 4, and 5,Fig. 3 showing a foot just entering the ground, Fig. 4 a foot at itslowest point, and Fig. 5 a foot just leaving the ground. It will beclear from Fig. 4, that each foot, as it enters the ground, formstherein a depression having a rear face which, when the foot reaches itslowermost point, will be spaced from the rear face of the foot asindicated at 2%. This space provides clearance for the outer rear cornerof the foot as it leaves the depression in the progression of theroller. As a result, the outer rear corners of the feet do not pick upany soil. Moreover, the front face of the foot imparts to the front faceof the depression a conformation which will not be disturbed by theouter front corner of the foot as the latter leaves the depression. Thisis of material advantage, since it is the purpose of a tamping roller tocompact the soil, and if the feet disturbed the soil in their upwardmovement compaction of the soil would to that extent be interfered with.

In order to prevent slipping of any pair of bands l6 upon the outersurface of the drum, the drum is provided in the plane ofeach pair ofbands with diametrically opposite, outwardly projecting pins 25adaptedto enter holes 26 in the respective semi-circular bands. By providingeach band with a plurality of holes 26 spaced apart a distance equal toa fraction of the circumferential foot-spacing, it is possible to varythe extent to which the feet of the adjacent pairs of bands arestaggered.

The mounting of feet of the type above described upon the bands I6 andthe securing of such bands to the drum I2 by means which permits them tobe angularly adjusted constitutes the subject matter of my co-pendingapplication Serial No. 349,433 (now Patent No. 2,410,465), of which thepresent application is a division.

I claim as my invention:

1. In a tamping roller, a plurality of axially spaced, circumferentiallvextending series of tamping feet, each of said feet being at least asthick, axially of the roller, at its outer end as over the remainingportions of its radial extent and having circumferentially presentedside faces which are concavely curved so that each foot is narrower nearthe middle of its radial extent than at its ends.

2. The invention set forth in claim 1 with the addition that thenarrowest portion of each foot is located somewhat nearer to the innerend of the foot than to the outer end, the radius of curvature of theside faces of each foot gradually increasing from the inner end of thefoot to the outer end.

3. The invention set forth in claim 1 with the addition that thenarrowest portion of eachfoot is located somewhat nearer to the innerend of the foot than to the outer end.

I v EVERETT T. SMALL.

REFERENCES CITED Number Name Date Small Nov. 5. 1946 V

